Method of maintaining a constantly-open feeding-passage into the interior of molten baths.



F. O. STROMBORG. 'METHOD OF MAINTAINING A GONSTANTLY OPEN FEEDING PASSAGE INTO THE INTERIOR 0F MOLTEN BATHS.

APPLIGATION FILED JULY 8, 1907.

Patented Dec. 8, 1908.

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INVENTOFL v WITNESSES.

to be a UNITED I STATES, PATENT OFFICE.

FRITZ OSCAR STROMBORG, OF YOUNGSTOWN, OHIO.

METHOD ormm'ranmroa ooNs'rm'rLr-onm FEEDING-PASSAGE 11mm y X martin-:01 mon'rnn BATES;

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. Be it known"that IfiFnrrz Ososn Snow 3 sident of. Youngstown; in th and State oi -Ohio, have,

vu ful mpr vement in Met o s a Constan #0 1 Feeding-Passage intot at In erior of 0 ton ath and I d hereby ec are the following u b. ear, d. act de cription thereof; a r invention. relates to a. method; of m m m n open pass ,or-oommu w tion to the interior of moltz ibathg,

In many arts it isfdesirable to have an open communication orpassage to a molten; bath beneath e fwe f h latter, su h; for in:

' a as ondui tubesfor fe d ng into the bath flux s, ya loy ng ma erials e: ducing gases .or other substances, as well as many, other uses, One of the difliculties in mai ta gsucho n mmunicationorpassage is due to the act that t emolten bath backs into, the passa or tube-andsolidifies,

0 i QQz' aJthQrem, .t at clogging: such pas:

sa e.

Theobject of this invention is, to rovide a simple method'for mainta' .suc comirrespective of t e chagacter of the bath.

The invention consists essentially in providing in such pipe or passage a fluid pressure 'sufiiciently 'high to prevent the molten bath from entering the passage or tube.

In the accompan ing drawing Figure 1 is a vertical section t rough a metal reducing or melting furnace showing my invention applied'thereto; Fig. 2 is an enlarged sectional view of one of the feeding tubes, and Fig. 3 is an enlarged sectional view of the cap for closing the tap hole. I

The invention is shown applied to ametal melting furnace 1 which may be of any dealloying material, or any other sired construction, that shown being similar ,to an open hearth furnace, having the hearth 2 upon which is the molten bath 3. The tap hole is shown at 4 and two tubes 5 are shown for supplying the bath with ore fuel, flux,

desired substance.

The tubes 5 are shown as projecting down intothe bath so that their discharge ends are located in the interior of the bath in order to introduce the substance fed through them down in the bath. These tubes are covered with fire brick, fire clay, or other re-' fractoq with a pee hinged en times and i Patented Dec. 8, 1908-.

A material 6., and their. lower pu'efera ly are;formed; of-gra hite.- These tubes are shownasoonnecte td a 'suppiy M8, and arerovided with the gate, or cut-off valve 9. e also. are provided portion. 11 which can be swung out, of the .way to allowpokingdown into-the tubes Inasmuch as the ends of these tubes project down into. the-bath the latter or-.

y would-back up into the tubes andsolidiiy, orfreeze therein. To prevent this I maintain intthe slightly. in excess oi the pressure due to the. head of the bath. -The' pressure medium may be-of any-desired d such as air, or.

as, and may also, if desired, be heated, al- 1; ough this is 'not necessary. The source of fluid pressunemay. be connected to the interior of thetubes. in any suitableiway, such v hole .10- pro erably formed in a tubes a tfluid pressure ends 7 asthroughthe openingl2 inthe supply connection chamber 8, or through the 14 at a lower point. The flu1 pressure will be regulatedb ,any-suitablemeans, such as valves15, set at 1t can be maintained sufficiently high to sli htl exceed the pressure due. tothe head oft he ducin an decided. blast which would. agis tate t e, ath. The lower ends 7 of the tubes are preferably formed as mouth pieces ath butwithout pro-- so shaped as to form a bubble of air or gas and the current of air or gas will be such as to cause the formation of bubbles slowly,

which, when fully formed, escape and rise up through the bath,as indicated at 16. Generallyone to four bubbles per second indi? eats a sufiicient volume of air or gas to revent thebath from backing up intothe tu es, but not suflicient to agitate the bath to any material extent.

The same princi 1c is a lied to the tap hole 4, this as sh wn lea d mg slightl upwardly instead of being horizontal or downwardly, and at its outer end being provided with a cover 18 of any suitable construction, preferably formed with a groove 19' fitting over a fiange 20, so providmg a recess for a 'filling of cla or other material for rendering the joint su stantially airti ht. The cover can be closed and opened y any suitable means, such as a lever 21, and is provided with a fluid inlet pipe 22 which is connected to any suitable source of fluidpressure, such as air or gas, and acting in the same way as heretofore described to prevent entry of the l bath into the tap hole, said fluid holding the bath back andescaping at the mner end of the tap hole in theform of bubbles. The

methodof maintaininglan open tap hole is,

slight upward inclination, as s own inthe or a passage or pipe which is .per-' tap hole,

endicular, and all angles between these two. The method is easy of a plication and also of regulation as it is mere y necessary to maintam a suflicient pressure to cause a very slow bubblin of the air or other fluid through the bath. t is effective to prevent entry of the bath into the tube or passage, thus keeping the same always open for the purpose of either by gravity introducing material into the bath or drawing the bath itself from the furnace chamber, or permitting the esca e of ases out of the bath. While it has een shown and described particularly with refer ence to a metal melting furnace it is not lim-' ited in its use to that art, but can, as above stated, be applied in any art in which it is necessary or esirable to maintain an open passage mto a molten bath below the surface of the same.

What I claim is:

i 1. The method of mamtaining a constantly open feeding passage into the inte-' rior of a molten bath, consistin in providingapassage communicating wit the interior of the bath, and constantly maintaining in said passage fluid under pressure in excess of the pressure of the head of the bath but only sufficient to cause a slow bubbling of the pressure fluid through the bath.

2. The 'method of maintaining a 'constantly open feeding passage into the interior of a molten bath, consisting in roviding a passage arranged at an angle a ove the horizontal'and communicating with the bath below its surface, and constantly maintaining in said passage fluid under pressure in excess of the ressure of the head of the bath but only sufllcient to produce a slow bubbling of the pressure fluid through the bath.

3. The method of maintaining a constantly-open feeding passage into the interior of a molten bath, consisting in providing a passage communicating with the interior of the bath, maintaining in said passage fluid under' ressure, and regulating the pressure and volume of said fluid to slightly overbalance the pressure due to the head of the bath and produce only a slow bubbling of the pressure fluid through the bath.

4. The method of maintaining a constantly open feeding passage into the interior of a molten bath, consisting in providin passages communicating with the interior 0 the bath, and maintaining in each passage fluid under controllable pressure n excess of the pressure of the'head of the bath but only suflicient to cause a slow bubbling of the pressure fluid through the bath.

In testimony whereof, I the said FRITZ OSCAR STRoMBonG have hereunto set my hand.

FRITZ OSCAR STROMBORG. Witnesses: 1

W; W. MELANDER, v NrLs M. WESTON. 

